Astronaut Eye Problems Study Finds Cause of Space-Impaired Vision

U.S. astronaut Peggy Whitson prepares to blast off to the International Space Station, where prolonged visits have resulted in eye problems for the astronauts, according to a NASA study.(Kirill Kudryavtsev/AFP/Getty Images)

A new study has shed light on the reasons why two-thirds of astronauts that spend a significant amount of time in space have had problems with their eyes.

The study used MRI brain scans to study the brains of astronauts before and after long-duration missions on the International Space Station. Astronauts who flew on short-duration missions were used as a comparison, according to The Daily Mail.

Astronaut Scott Kelly experienced changes in his vision during his 1999 mission to the ISS and wore reading glasses to correct the problem in 2007.

His mission from 2010 to 2011 also involved vision difficulties, but they resolved themselves within a few months of returning to Earth, The Daily Mail reported.

The study revealed that long-duration astronauts had more flattened eyeballs and more optic nerve swelling when they returned to Earth, compared with those on shorter missions.

The long-duration astronauts also had more spinal fluid in the areas of the brain where CSF fluid is produced and more fluid around the optic nerve, according to the Daily Mail.

The syndrome, known as visual impairment intracranial pressure, is of concern to NASA because of longer-term missions, including missions to Mars, being planned for the future. It is important for NASA scientists to understand what happens to the eyes when in space for a prolonged period of time, according to the BBC.

The new research is being presented today at the annual Radiological Society of North America meeting in Chicago. NASA has given lead study author Noam Alperin a $600,000 grant for further study of VIIP.